Doors covered with plastic sheets which are embossed with decorative patterns or figures by means of thermoplastic deformation art for closing the entrance to a building, room, cupboard, etc. are well known in the prior art. Referring to FIG. 2, a thermoplastic sheet 10 of a suitable thickness and about the size of a major side wall of a board of a door is used and then heated to the plastic deformable state by a heater or suitable number of infrared heaters located on the top and bottom of the sheet 10. The thermoplastic sheet 10 may be moved relative to the heaters or the heaters may be moved relative to the sheet 10 so as to evenly distribute the heating effect to the sheet 10 to achieve a uniform deformable plastic state.
The thermoplastic sheet 10 is then placed between a male die 11 and a female die 12 and further sealed therebetween. The metal block of the male die 11 is cut with desired pattern or FIG. 111 and provided with a plurality of passages 110 extending downwardly to connect an air conduit 13 which is connected to a vacuum pump (not shown). The vacuum pump will create a vacuum in the chamber in top portion of the male die 11 to form desired pattern or FIG. 102 in the sheet 10 corresponding to the shapes cut in the male die 11 by creating an excess of pressure on the upper face of the sheet 10. After this is accomplished, the thermoplastic sheet 11 is then removed form the molds 11 and 12 into the open air for air cooling.
Two such thermoplastic sheets 10 both of a size can be attached to major opposed sides of the board of the door by means of adhesives.
It is found that the embossed patterns or figures of the thermoplastic sheets attached to doors are easy to be fractured in transport as doors generally stacked up in container or aboard. To alleviate this problem sufficient stuffing arranged among doors is necessary to prevent the embossed patterns or figures from fracturing or undesired deformations caused by loading pressure, and that is obviously costly and labour consuming.
The present invention provides an improved door covered with thermoplastic sheets each of which has a concavity surface for been shaped or embossed with decorative design such as pattern or figure.
Accordingly, it is an object of the present invention to provide an improved door with its concavity surface for securing designs shaped or embossed therein from being fractured.
It is a further object of the present invention to provide an improved door with a concavity surface which is easy to pack and labour and space savings in packaging.